1. Field of the Invention
The present invention relates to a screen printing machine.
2. Description of the Prior Art
Hitherto, in a screen printing machine in which a stencil paper is wrapped around a plate cylinder to conduct a printing operation, after completion of the printing operation, a waste stencil paper is manually peeled from the plate cylinder to cause a machine operator to ink his hands and clothes.
In order to prevent the machine operator from inking his hands and clothes in a printing-plate discharge operation of the screen printing machine, there has been developed a method for automatically discharging the waste printing plate from the printing machine, in which method an end portion of the waste printing plate is clamped between a pair of rollers and peeled from the plate cylinder of the printing machine as such rollers are rotatably driven. In the method, the thus peeled printing plate or waste stencil paper is not individually carried to a dump yard, but deposited in a waste-paper container of the printing machine by a predetermined number of waste stencil papers. The waste-paper container is carried to the dump yard when filled with the waste stencil papers.
However, in case that the capacity of the waste-paper container is small, the waste stencil papers received in the container must be frequently removed from the container. Neglect of such frequent removal of the waste stencil papers leads to jamming of the printing machine, while such frequent removal of the waste stencil papers causes the machine operator to ink his hands and clothes.
In order to resolve the above problems, when a large-sized waste-paper container is employed in the printing machine, it is difficult to find a space for receiving such large-sized container in the vicinity of the printing machine. As a result, in this case, the waste-paper container is installed in a position spaced apart from the printing machine by a relatively long distance, to which container the waste stencil papers are carried from the printing machine through a long-transfer passage. However, such long-transfer passage is often clogged with the waste stencil papers. In addition, the large-sized waste-paper container causes an environmental problem due to a disgusting odor of a large number of the waste stencil papers deposited therein.
Further, in the above case, the waste-paper container must be cleared when filled with the waste stencil papers. However, it is cumbersome for the machine operator to monitor a filling-condition the waste-paper container. When the waste stencil papers are disorderly deposited in the waste-paper container, the container is filled with a relatively-small amount of waste stencil papers. As described above, the conventional screen printing machine suffers from many problems.